Methods and apparatus for the deposition of semiconducting and insulating films in the manufacture of semiconductor devices are either batch or continuous systems. In such systems one or more substrates are arranged in a deposition chamber so that their principal faces, i.e., those being coated, are substantially coplanar. The deposition is effected by the decomposition of a reactive gas which may be activated in several ways. The first of two more usual ways is by heating the gas sufficiently as is done in the Low Pressure Chemical Vapor Deposition Method (LPCVD) and the second is by subjecting the gas to a glow discharge. One variation of the latter is known in the art as the positive column glow discharge method wherein a pair of electrodes having a potential impressed thereon, one electrode being positioned on each side of the substrates, activate a reactant gas such as silane whereupon a glow discharge is initiated in the space between the electrodes resulting in deposition of amorphous silicon on the surfaces of the substrates. See, for example, U.S. Pat. No. 4,033,287, issued July 5, 1977 to Alexander, Jr. et al, which discloses a glow discharge reactor apparatus of this type.
Existing types of apparatus for continuous deposition of films onto substrates utilize a coplanar orientation of the principal faces of the substrates to be coated. One form of such a system is described in U.S. Pat. No. 4,313,254, issued Feb. 2, 1982 to Feldman et al. Feldman provides a series of connected vacuum chambers for performing various processing steps on a substrate as it is passed along a transport track which traverses each chamber. Substrates in a stack are introduced to the system through a loadlock valve and are individually placed on the support track so that their principal faces are parallel to the direction of travel along the transport track. With this arrangement the amount of substrate material that can be accommodated at any one time within an individual deposition chamber is quite limited, thereby limiting production throughput of the system. Further, vapor baffles that form separators between the deposition chambers are of the stationary type and rely on close proximity with the principal faces of the substrates being coated to prevent cross contamination between chambers. Steps must be taken to assure that the baffles clear the moving substrate surfaces to prevent damage thereto.
What is needed is an apparatus for large-scale continuous deposition of substrates having improved throughput of coated substrates and baffles that effectively prevent cross contamination between deposition chambers.